Definition of Thermal Conductivity
Thermal conductivity (λ with the unit W/(m•K)) describes the transport of energy – in the form of heat – through a body of mass as the result of a temperature gradient (see fig. 1). According to the second law of thermodynamics, heat always flows in the direction of the lower temperature.
Where
a: Thermal diffusivity
cp: Specific heat capacity
ρ: Density
An overview of the thermal conductivity for various materials is shown in figure 2.